Last name Kasain (Kasain 
, Касаин 
) , in all the world, is a very rare surname. The surname Kasain is habitual in Malaysia, where it is a very rare surname, Philippines, where it is an extremely rare surname, and India. Likewise, Kasain is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kasain | Philippines, Malaysia, India, United States, Thailand |
| Касаин | Kazakhstan, Russia |